Garage door opening spring

[DaveReading]

Fresh from my recent plumbing successes(!), I’ve turned my attention to my garage door, which has been causing problems recently.

It’s an elderly Cardale Mk2 or Mk3 (not sure what the difference is) up-and-over canopy door which opens with the help of a humungous drum spring (akin to a giant watch spring) mounted centrally above the door and which pulls the door up via cables (just visible in the photo) and pulleys.

The cables tend to stretch over time and become less effective. so the plan is to replace them, spares being readily available.

Obviously the cables can’t be removed or replaced while under tension, so the recommended procedure is to tighten the spring a bit more by pulling on the cable(s) until the locking holes on the drum and its bracket line up so that a pin or nail can be inserted in order to generate some slack in the cables and also prevent the spring unwinding completely.

The problem is how to exert enough pull on the cables to wind the spring up further, bearing in mind that it’s already storing enough force to lift the door. It needs about a quarter turn or so further to line up the locking holes, but I’m not strong enough to do that without some means of devising a mechanical advantage.

Does anyone have experience with these drum springs? Any suggestions as to how to wind it up further?

 

[classic33]

https://www.garage-door-spares.co.uk/cardale-CAR0040-fit.htm

 

[DaveReading]

https://www.garage-door-spares.co.uk/cardale-CAR0040-fit.htm

Yes, I've seen that, thanks. It helpfully says "pull on one of the cables".

I'd better get down the gym ...

 

[bikingdad90]

Garage doors are flipping heavy! I found out when our up and over came out the side guards and wouldn’t shut or open properly.
It took three of us to lift and get it back into place so that we could then fix the guards and retighten the springs which unloaded when it came away.

The springs have a massive load on them and I suggest unless you are confident it is a job best left to a professional fitter so that you don’t seriously injure yourself.

 

[DaveReading]

The springs have a massive load on them and I suggest unless you are confident it is a job best left to a professional fitter so that you don’t seriously injure yourself.

Thanks, I'm tending towards getting someone to do it, mostly because of pressure from SWMBO.

That said, I've ordered the bits I need (cables and new rollers) although that doesn't preclude having them fitted by a professional. I also took the opportunity to invest in some new safety goggles and heavy-duty gloves.

Interestingly, after I'd cleaned up years of accumulated grease and crud from the roller channels and hinges, the door now opens of its own accord when released (though not that far) even with just one of the two side cables connected.

My main immediate concern is whether I can open it enough for the time being to get my bike out.

 

[Alex H]

Suggest this for bedtime reading

https://garageinsiders.com/garage-door-springs-dangerous/

 

[DaveReading]

Suggest this for bedtime reading

https://garageinsiders.com/garage-door-springs-dangerous/

Thanks for that.

If my door was powered by either of the spring types in that article, or indeed any kind of exposed spring, rest assured I wouldn't even be considering working on it.

 

[fossyant]

Mine has a big spring that sits above the whole width of the door. I've replaced both cables (bought some generic cable from B&Q and some locking clips). I found shutting the door (you inside) releases most of the tension from that type. I usually shoved in a screwdriver and relieved a bit more tension (rotated the driver)then fitted the cables.

Yours looks somewhat more complicated.

 

[DaveReading]

Mine has a big spring that sits above the whole width of the door. I've replaced both cables (bought some generic cable from B&Q and some locking clips). I found shutting the door (you inside) releases most of the tension from that type. I usually shoved in a screwdriver and relieved a bit more tension (rotated the driver)then fitted the cables.

Yours looks somewhat more complicated.

Strangely enough, it's much simpler than a lot of the arrangements I've seen, especially those for doors that retract (as opposed to canopy ones).

It's essentially a capstan powered by an internal spring. The capstan drives two cables that run left and right from it and, via pulleys, move vertically to raise and lower the door.

 

[DaveReading]

A belated postscript to the door saga – new rollers and cables now fitted, with a couple of gotchas en route.

The problem with not being able to wind up the drum spring enough to line up the locking pin holes and create slack in the cables (see my earlier post) was a showstopper until I had a lightbulb moment.

A cylinder that’s hard to turn? In my dim and distant memory I recalled car oil filters that were hard to remove – in my cheapskate days I would just hammer a screwdriver through them to give some leverage, but eventually I invested in a strap wrench (a distant cousin of chain whip). I didn’t have one long enough to fit round the drum spring, but Amazon did.

With the spring safely locked, it was then a trivial task to unhook the old cables and fit the new ones. One final gotcha when the door wouldn’t open because once closed it was trapping the cables between it and the support struts, but a quick reroute fixed that.

So I once more have an opening door and can get my bike out. Morning ride tomorrow to celebrate!

I would stress again (as other posters have mentioned) that had this been an extending or torsion spring instead of an enclosed mainspring, I would have sought professional help and would advise anyone in a similar situation to do so as well.